The following abbreviations that may be found in the specification and/or the drawing figures are defined as follows:
802.11 IEEE Std 802.11-2007 and predecessor and successor standards
CE Control Element
DCF distributed coordination function
DIFS distributed interframe space
ISM industrial-scientific-medical
LCID logical channel ID
MAC medium access control
ms millisecond
PC point coordinator
PCF point coordination function
PIFS PCF interframe space
SCC secondary component carrier
SIPS short interframe space
UCI uplink control information
UE user equipment
WM wireless medium
WIFI wireless fidelity
Interest in wireless communication, particularly personal wireless communication, has increased more and more during the last few decades, and user demand for the ability to transmit and receive information wirelessly has proven insatiable. More and more users wish to spend more and more of their time communicating with one another, sharing data with others, and receiving data made available to the public at large or to large groups of users, so that serving the simultaneous activities of these users while providing an acceptable quality of service to each user has proven more and more challenging. Manufacturers and operators of wireless communication systems such as cellular networks have gone to great lengths to increase the data that can be carried in the portion of the radiofrequency spectrum allocated to them. Continued advances in the efficient use of the radiofrequency spectrum to carry data have led from the first wireless transmissions in the 1800's to the present day's ubiquitous presence of wireless data communication in every aspect of everyday life.